1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Cryptographic API.
4 *
5 * s390 implementation of the DES Cipher Algorithm.
6 *
7 * Copyright IBM Corp. 2003, 2011
8 * Author(s): Thomas Spatzier
9 * Jan Glauber (jan.glauber@de.ibm.com)
10 */
11
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/cpufeature.h>
15 #include <linux/crypto.h>
16 #include <linux/fips.h>
17 #include <linux/mutex.h>
18 #include <crypto/algapi.h>
19 #include <crypto/internal/des.h>
20 #include <crypto/internal/skcipher.h>
21 #include <asm/cpacf.h>
22
23 #define DES3_KEY_SIZE (3 * DES_KEY_SIZE)
24
25 static u8 *ctrblk;
26 static DEFINE_MUTEX(ctrblk_lock);
27
28 static cpacf_mask_t km_functions, kmc_functions, kmctr_functions;
29
30 struct s390_des_ctx {
31 u8 iv[DES_BLOCK_SIZE];
32 u8 key[DES3_KEY_SIZE];
33 };
34
des_setkey(struct crypto_tfm * tfm,const u8 * key,unsigned int key_len)35 static int des_setkey(struct crypto_tfm *tfm, const u8 *key,
36 unsigned int key_len)
37 {
38 struct s390_des_ctx *ctx = crypto_tfm_ctx(tfm);
39 int err;
40
41 err = crypto_des_verify_key(tfm, key);
42 if (err)
43 return err;
44
45 memcpy(ctx->key, key, key_len);
46 return 0;
47 }
48
des_setkey_skcipher(struct crypto_skcipher * tfm,const u8 * key,unsigned int key_len)49 static int des_setkey_skcipher(struct crypto_skcipher *tfm, const u8 *key,
50 unsigned int key_len)
51 {
52 return des_setkey(crypto_skcipher_tfm(tfm), key, key_len);
53 }
54
s390_des_encrypt(struct crypto_tfm * tfm,u8 * out,const u8 * in)55 static void s390_des_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
56 {
57 struct s390_des_ctx *ctx = crypto_tfm_ctx(tfm);
58
59 cpacf_km(CPACF_KM_DEA, ctx->key, out, in, DES_BLOCK_SIZE);
60 }
61
s390_des_decrypt(struct crypto_tfm * tfm,u8 * out,const u8 * in)62 static void s390_des_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
63 {
64 struct s390_des_ctx *ctx = crypto_tfm_ctx(tfm);
65
66 cpacf_km(CPACF_KM_DEA | CPACF_DECRYPT,
67 ctx->key, out, in, DES_BLOCK_SIZE);
68 }
69
70 static struct crypto_alg des_alg = {
71 .cra_name = "des",
72 .cra_driver_name = "des-s390",
73 .cra_priority = 300,
74 .cra_flags = CRYPTO_ALG_TYPE_CIPHER,
75 .cra_blocksize = DES_BLOCK_SIZE,
76 .cra_ctxsize = sizeof(struct s390_des_ctx),
77 .cra_module = THIS_MODULE,
78 .cra_u = {
79 .cipher = {
80 .cia_min_keysize = DES_KEY_SIZE,
81 .cia_max_keysize = DES_KEY_SIZE,
82 .cia_setkey = des_setkey,
83 .cia_encrypt = s390_des_encrypt,
84 .cia_decrypt = s390_des_decrypt,
85 }
86 }
87 };
88
ecb_desall_crypt(struct skcipher_request * req,unsigned long fc)89 static int ecb_desall_crypt(struct skcipher_request *req, unsigned long fc)
90 {
91 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
92 struct s390_des_ctx *ctx = crypto_skcipher_ctx(tfm);
93 struct skcipher_walk walk;
94 unsigned int nbytes, n;
95 int ret;
96
97 ret = skcipher_walk_virt(&walk, req, false);
98 while ((nbytes = walk.nbytes) != 0) {
99 /* only use complete blocks */
100 n = nbytes & ~(DES_BLOCK_SIZE - 1);
101 cpacf_km(fc, ctx->key, walk.dst.virt.addr,
102 walk.src.virt.addr, n);
103 ret = skcipher_walk_done(&walk, nbytes - n);
104 }
105 return ret;
106 }
107
cbc_desall_crypt(struct skcipher_request * req,unsigned long fc)108 static int cbc_desall_crypt(struct skcipher_request *req, unsigned long fc)
109 {
110 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
111 struct s390_des_ctx *ctx = crypto_skcipher_ctx(tfm);
112 struct skcipher_walk walk;
113 unsigned int nbytes, n;
114 int ret;
115 struct {
116 u8 iv[DES_BLOCK_SIZE];
117 u8 key[DES3_KEY_SIZE];
118 } param;
119
120 ret = skcipher_walk_virt(&walk, req, false);
121 if (ret)
122 return ret;
123 memcpy(param.iv, walk.iv, DES_BLOCK_SIZE);
124 memcpy(param.key, ctx->key, DES3_KEY_SIZE);
125 while ((nbytes = walk.nbytes) != 0) {
126 /* only use complete blocks */
127 n = nbytes & ~(DES_BLOCK_SIZE - 1);
128 cpacf_kmc(fc, ¶m, walk.dst.virt.addr,
129 walk.src.virt.addr, n);
130 memcpy(walk.iv, param.iv, DES_BLOCK_SIZE);
131 ret = skcipher_walk_done(&walk, nbytes - n);
132 }
133 return ret;
134 }
135
ecb_des_encrypt(struct skcipher_request * req)136 static int ecb_des_encrypt(struct skcipher_request *req)
137 {
138 return ecb_desall_crypt(req, CPACF_KM_DEA);
139 }
140
ecb_des_decrypt(struct skcipher_request * req)141 static int ecb_des_decrypt(struct skcipher_request *req)
142 {
143 return ecb_desall_crypt(req, CPACF_KM_DEA | CPACF_DECRYPT);
144 }
145
146 static struct skcipher_alg ecb_des_alg = {
147 .base.cra_name = "ecb(des)",
148 .base.cra_driver_name = "ecb-des-s390",
149 .base.cra_priority = 400, /* combo: des + ecb */
150 .base.cra_blocksize = DES_BLOCK_SIZE,
151 .base.cra_ctxsize = sizeof(struct s390_des_ctx),
152 .base.cra_module = THIS_MODULE,
153 .min_keysize = DES_KEY_SIZE,
154 .max_keysize = DES_KEY_SIZE,
155 .setkey = des_setkey_skcipher,
156 .encrypt = ecb_des_encrypt,
157 .decrypt = ecb_des_decrypt,
158 };
159
cbc_des_encrypt(struct skcipher_request * req)160 static int cbc_des_encrypt(struct skcipher_request *req)
161 {
162 return cbc_desall_crypt(req, CPACF_KMC_DEA);
163 }
164
cbc_des_decrypt(struct skcipher_request * req)165 static int cbc_des_decrypt(struct skcipher_request *req)
166 {
167 return cbc_desall_crypt(req, CPACF_KMC_DEA | CPACF_DECRYPT);
168 }
169
170 static struct skcipher_alg cbc_des_alg = {
171 .base.cra_name = "cbc(des)",
172 .base.cra_driver_name = "cbc-des-s390",
173 .base.cra_priority = 400, /* combo: des + cbc */
174 .base.cra_blocksize = DES_BLOCK_SIZE,
175 .base.cra_ctxsize = sizeof(struct s390_des_ctx),
176 .base.cra_module = THIS_MODULE,
177 .min_keysize = DES_KEY_SIZE,
178 .max_keysize = DES_KEY_SIZE,
179 .ivsize = DES_BLOCK_SIZE,
180 .setkey = des_setkey_skcipher,
181 .encrypt = cbc_des_encrypt,
182 .decrypt = cbc_des_decrypt,
183 };
184
185 /*
186 * RFC2451:
187 *
188 * For DES-EDE3, there is no known need to reject weak or
189 * complementation keys. Any weakness is obviated by the use of
190 * multiple keys.
191 *
192 * However, if the first two or last two independent 64-bit keys are
193 * equal (k1 == k2 or k2 == k3), then the DES3 operation is simply the
194 * same as DES. Implementers MUST reject keys that exhibit this
195 * property.
196 *
197 * In fips mode additionally check for all 3 keys are unique.
198 *
199 */
des3_setkey(struct crypto_tfm * tfm,const u8 * key,unsigned int key_len)200 static int des3_setkey(struct crypto_tfm *tfm, const u8 *key,
201 unsigned int key_len)
202 {
203 struct s390_des_ctx *ctx = crypto_tfm_ctx(tfm);
204 int err;
205
206 err = crypto_des3_ede_verify_key(tfm, key);
207 if (err)
208 return err;
209
210 memcpy(ctx->key, key, key_len);
211 return 0;
212 }
213
des3_setkey_skcipher(struct crypto_skcipher * tfm,const u8 * key,unsigned int key_len)214 static int des3_setkey_skcipher(struct crypto_skcipher *tfm, const u8 *key,
215 unsigned int key_len)
216 {
217 return des3_setkey(crypto_skcipher_tfm(tfm), key, key_len);
218 }
219
des3_encrypt(struct crypto_tfm * tfm,u8 * dst,const u8 * src)220 static void des3_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
221 {
222 struct s390_des_ctx *ctx = crypto_tfm_ctx(tfm);
223
224 cpacf_km(CPACF_KM_TDEA_192, ctx->key, dst, src, DES_BLOCK_SIZE);
225 }
226
des3_decrypt(struct crypto_tfm * tfm,u8 * dst,const u8 * src)227 static void des3_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
228 {
229 struct s390_des_ctx *ctx = crypto_tfm_ctx(tfm);
230
231 cpacf_km(CPACF_KM_TDEA_192 | CPACF_DECRYPT,
232 ctx->key, dst, src, DES_BLOCK_SIZE);
233 }
234
235 static struct crypto_alg des3_alg = {
236 .cra_name = "des3_ede",
237 .cra_driver_name = "des3_ede-s390",
238 .cra_priority = 300,
239 .cra_flags = CRYPTO_ALG_TYPE_CIPHER,
240 .cra_blocksize = DES_BLOCK_SIZE,
241 .cra_ctxsize = sizeof(struct s390_des_ctx),
242 .cra_module = THIS_MODULE,
243 .cra_u = {
244 .cipher = {
245 .cia_min_keysize = DES3_KEY_SIZE,
246 .cia_max_keysize = DES3_KEY_SIZE,
247 .cia_setkey = des3_setkey,
248 .cia_encrypt = des3_encrypt,
249 .cia_decrypt = des3_decrypt,
250 }
251 }
252 };
253
ecb_des3_encrypt(struct skcipher_request * req)254 static int ecb_des3_encrypt(struct skcipher_request *req)
255 {
256 return ecb_desall_crypt(req, CPACF_KM_TDEA_192);
257 }
258
ecb_des3_decrypt(struct skcipher_request * req)259 static int ecb_des3_decrypt(struct skcipher_request *req)
260 {
261 return ecb_desall_crypt(req, CPACF_KM_TDEA_192 | CPACF_DECRYPT);
262 }
263
264 static struct skcipher_alg ecb_des3_alg = {
265 .base.cra_name = "ecb(des3_ede)",
266 .base.cra_driver_name = "ecb-des3_ede-s390",
267 .base.cra_priority = 400, /* combo: des3 + ecb */
268 .base.cra_blocksize = DES_BLOCK_SIZE,
269 .base.cra_ctxsize = sizeof(struct s390_des_ctx),
270 .base.cra_module = THIS_MODULE,
271 .min_keysize = DES3_KEY_SIZE,
272 .max_keysize = DES3_KEY_SIZE,
273 .setkey = des3_setkey_skcipher,
274 .encrypt = ecb_des3_encrypt,
275 .decrypt = ecb_des3_decrypt,
276 };
277
cbc_des3_encrypt(struct skcipher_request * req)278 static int cbc_des3_encrypt(struct skcipher_request *req)
279 {
280 return cbc_desall_crypt(req, CPACF_KMC_TDEA_192);
281 }
282
cbc_des3_decrypt(struct skcipher_request * req)283 static int cbc_des3_decrypt(struct skcipher_request *req)
284 {
285 return cbc_desall_crypt(req, CPACF_KMC_TDEA_192 | CPACF_DECRYPT);
286 }
287
288 static struct skcipher_alg cbc_des3_alg = {
289 .base.cra_name = "cbc(des3_ede)",
290 .base.cra_driver_name = "cbc-des3_ede-s390",
291 .base.cra_priority = 400, /* combo: des3 + cbc */
292 .base.cra_blocksize = DES_BLOCK_SIZE,
293 .base.cra_ctxsize = sizeof(struct s390_des_ctx),
294 .base.cra_module = THIS_MODULE,
295 .min_keysize = DES3_KEY_SIZE,
296 .max_keysize = DES3_KEY_SIZE,
297 .ivsize = DES_BLOCK_SIZE,
298 .setkey = des3_setkey_skcipher,
299 .encrypt = cbc_des3_encrypt,
300 .decrypt = cbc_des3_decrypt,
301 };
302
__ctrblk_init(u8 * ctrptr,u8 * iv,unsigned int nbytes)303 static unsigned int __ctrblk_init(u8 *ctrptr, u8 *iv, unsigned int nbytes)
304 {
305 unsigned int i, n;
306
307 /* align to block size, max. PAGE_SIZE */
308 n = (nbytes > PAGE_SIZE) ? PAGE_SIZE : nbytes & ~(DES_BLOCK_SIZE - 1);
309 memcpy(ctrptr, iv, DES_BLOCK_SIZE);
310 for (i = (n / DES_BLOCK_SIZE) - 1; i > 0; i--) {
311 memcpy(ctrptr + DES_BLOCK_SIZE, ctrptr, DES_BLOCK_SIZE);
312 crypto_inc(ctrptr + DES_BLOCK_SIZE, DES_BLOCK_SIZE);
313 ctrptr += DES_BLOCK_SIZE;
314 }
315 return n;
316 }
317
ctr_desall_crypt(struct skcipher_request * req,unsigned long fc)318 static int ctr_desall_crypt(struct skcipher_request *req, unsigned long fc)
319 {
320 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
321 struct s390_des_ctx *ctx = crypto_skcipher_ctx(tfm);
322 u8 buf[DES_BLOCK_SIZE], *ctrptr;
323 struct skcipher_walk walk;
324 unsigned int n, nbytes;
325 int ret, locked;
326
327 locked = mutex_trylock(&ctrblk_lock);
328
329 ret = skcipher_walk_virt(&walk, req, false);
330 while ((nbytes = walk.nbytes) >= DES_BLOCK_SIZE) {
331 n = DES_BLOCK_SIZE;
332 if (nbytes >= 2*DES_BLOCK_SIZE && locked)
333 n = __ctrblk_init(ctrblk, walk.iv, nbytes);
334 ctrptr = (n > DES_BLOCK_SIZE) ? ctrblk : walk.iv;
335 cpacf_kmctr(fc, ctx->key, walk.dst.virt.addr,
336 walk.src.virt.addr, n, ctrptr);
337 if (ctrptr == ctrblk)
338 memcpy(walk.iv, ctrptr + n - DES_BLOCK_SIZE,
339 DES_BLOCK_SIZE);
340 crypto_inc(walk.iv, DES_BLOCK_SIZE);
341 ret = skcipher_walk_done(&walk, nbytes - n);
342 }
343 if (locked)
344 mutex_unlock(&ctrblk_lock);
345 /* final block may be < DES_BLOCK_SIZE, copy only nbytes */
346 if (nbytes) {
347 cpacf_kmctr(fc, ctx->key, buf, walk.src.virt.addr,
348 DES_BLOCK_SIZE, walk.iv);
349 memcpy(walk.dst.virt.addr, buf, nbytes);
350 crypto_inc(walk.iv, DES_BLOCK_SIZE);
351 ret = skcipher_walk_done(&walk, 0);
352 }
353 return ret;
354 }
355
ctr_des_crypt(struct skcipher_request * req)356 static int ctr_des_crypt(struct skcipher_request *req)
357 {
358 return ctr_desall_crypt(req, CPACF_KMCTR_DEA);
359 }
360
361 static struct skcipher_alg ctr_des_alg = {
362 .base.cra_name = "ctr(des)",
363 .base.cra_driver_name = "ctr-des-s390",
364 .base.cra_priority = 400, /* combo: des + ctr */
365 .base.cra_blocksize = 1,
366 .base.cra_ctxsize = sizeof(struct s390_des_ctx),
367 .base.cra_module = THIS_MODULE,
368 .min_keysize = DES_KEY_SIZE,
369 .max_keysize = DES_KEY_SIZE,
370 .ivsize = DES_BLOCK_SIZE,
371 .setkey = des_setkey_skcipher,
372 .encrypt = ctr_des_crypt,
373 .decrypt = ctr_des_crypt,
374 .chunksize = DES_BLOCK_SIZE,
375 };
376
ctr_des3_crypt(struct skcipher_request * req)377 static int ctr_des3_crypt(struct skcipher_request *req)
378 {
379 return ctr_desall_crypt(req, CPACF_KMCTR_TDEA_192);
380 }
381
382 static struct skcipher_alg ctr_des3_alg = {
383 .base.cra_name = "ctr(des3_ede)",
384 .base.cra_driver_name = "ctr-des3_ede-s390",
385 .base.cra_priority = 400, /* combo: des3 + ede */
386 .base.cra_blocksize = 1,
387 .base.cra_ctxsize = sizeof(struct s390_des_ctx),
388 .base.cra_module = THIS_MODULE,
389 .min_keysize = DES3_KEY_SIZE,
390 .max_keysize = DES3_KEY_SIZE,
391 .ivsize = DES_BLOCK_SIZE,
392 .setkey = des3_setkey_skcipher,
393 .encrypt = ctr_des3_crypt,
394 .decrypt = ctr_des3_crypt,
395 .chunksize = DES_BLOCK_SIZE,
396 };
397
398 static struct crypto_alg *des_s390_algs_ptr[2];
399 static int des_s390_algs_num;
400 static struct skcipher_alg *des_s390_skciphers_ptr[6];
401 static int des_s390_skciphers_num;
402
des_s390_register_alg(struct crypto_alg * alg)403 static int des_s390_register_alg(struct crypto_alg *alg)
404 {
405 int ret;
406
407 ret = crypto_register_alg(alg);
408 if (!ret)
409 des_s390_algs_ptr[des_s390_algs_num++] = alg;
410 return ret;
411 }
412
des_s390_register_skcipher(struct skcipher_alg * alg)413 static int des_s390_register_skcipher(struct skcipher_alg *alg)
414 {
415 int ret;
416
417 ret = crypto_register_skcipher(alg);
418 if (!ret)
419 des_s390_skciphers_ptr[des_s390_skciphers_num++] = alg;
420 return ret;
421 }
422
des_s390_exit(void)423 static void des_s390_exit(void)
424 {
425 while (des_s390_algs_num--)
426 crypto_unregister_alg(des_s390_algs_ptr[des_s390_algs_num]);
427 while (des_s390_skciphers_num--)
428 crypto_unregister_skcipher(des_s390_skciphers_ptr[des_s390_skciphers_num]);
429 if (ctrblk)
430 free_page((unsigned long) ctrblk);
431 }
432
des_s390_init(void)433 static int __init des_s390_init(void)
434 {
435 int ret;
436
437 /* Query available functions for KM, KMC and KMCTR */
438 cpacf_query(CPACF_KM, &km_functions);
439 cpacf_query(CPACF_KMC, &kmc_functions);
440 cpacf_query(CPACF_KMCTR, &kmctr_functions);
441
442 if (cpacf_test_func(&km_functions, CPACF_KM_DEA)) {
443 ret = des_s390_register_alg(&des_alg);
444 if (ret)
445 goto out_err;
446 ret = des_s390_register_skcipher(&ecb_des_alg);
447 if (ret)
448 goto out_err;
449 }
450 if (cpacf_test_func(&kmc_functions, CPACF_KMC_DEA)) {
451 ret = des_s390_register_skcipher(&cbc_des_alg);
452 if (ret)
453 goto out_err;
454 }
455 if (cpacf_test_func(&km_functions, CPACF_KM_TDEA_192)) {
456 ret = des_s390_register_alg(&des3_alg);
457 if (ret)
458 goto out_err;
459 ret = des_s390_register_skcipher(&ecb_des3_alg);
460 if (ret)
461 goto out_err;
462 }
463 if (cpacf_test_func(&kmc_functions, CPACF_KMC_TDEA_192)) {
464 ret = des_s390_register_skcipher(&cbc_des3_alg);
465 if (ret)
466 goto out_err;
467 }
468
469 if (cpacf_test_func(&kmctr_functions, CPACF_KMCTR_DEA) ||
470 cpacf_test_func(&kmctr_functions, CPACF_KMCTR_TDEA_192)) {
471 ctrblk = (u8 *) __get_free_page(GFP_KERNEL);
472 if (!ctrblk) {
473 ret = -ENOMEM;
474 goto out_err;
475 }
476 }
477
478 if (cpacf_test_func(&kmctr_functions, CPACF_KMCTR_DEA)) {
479 ret = des_s390_register_skcipher(&ctr_des_alg);
480 if (ret)
481 goto out_err;
482 }
483 if (cpacf_test_func(&kmctr_functions, CPACF_KMCTR_TDEA_192)) {
484 ret = des_s390_register_skcipher(&ctr_des3_alg);
485 if (ret)
486 goto out_err;
487 }
488
489 return 0;
490 out_err:
491 des_s390_exit();
492 return ret;
493 }
494
495 module_cpu_feature_match(S390_CPU_FEATURE_MSA, des_s390_init);
496 module_exit(des_s390_exit);
497
498 MODULE_ALIAS_CRYPTO("des");
499 MODULE_ALIAS_CRYPTO("des3_ede");
500
501 MODULE_LICENSE("GPL");
502 MODULE_DESCRIPTION("DES & Triple DES EDE Cipher Algorithms");
503